This application relates to non-metabolizable analogs of clomiphene which have been shown to be effective in reducing the proliferation of cell lines known to be resistant to tamoxifen, a known anti-tumor agent. Two of the compounds specifically demonstrated to be useful according to the claimed invention have been disclosed previously. Murphy and Sutherland in the Journal of Clinical Endocrinology and Metabolism, 57(2), 373, disclose that compounds of this invention were also effective in inhibiting the growth of MCF-7 cells, a cell line sensitive to tamoxifen. In CA:64 8081, a method of preparing 3-[p-2-chloro-l,2-diphenylvinyl)phenyl]-N,N-diethyl-hydro-chloride was disclosed. At that time the compound was alleged to be useful in the treatment of gynecological defects and hypercholesterolemia. In CA:63 535h, the same compound is presented and its use as an inhibitor of pituitary gonadotropin was disclosed.